Ntp, darken the color of the overScroll for the RecyclerView

chrome/android/java/res/values/dimens.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2014 The Chromium Authors. All rights reserved.
      Use of this source code is governed by a BSD-style license that can be
      found in the LICENSE file. -->
 
 <resources>
     <!-- Connection info popup dimensions -->
     <dimen name="connection_info_padding_wide">24dp</dimen>
     <dimen name="connection_info_padding_thin">16dp</dimen>
 
@@ skipping 269 matching lines @@
     <dimen name="ntp_search_box_material_extra_width">4dp</dimen>
     <dimen name="ntp_search_box_material_padding_top">3dp</dimen>
     <dimen name="ntp_search_box_material_padding_bottom">3dp</dimen>
     <dimen name="ntp_search_box_material_padding_left">2dp</dimen>
     <dimen name="ntp_search_box_material_padding_right">2dp</dimen>
     <dimen name="ntp_search_box_transition_length">16dp</dimen>
     <dimen name="ntp_list_item_padding">16dp</dimen>
     <dimen name="ntp_list_item_min_height">48dp</dimen>
     <dimen name="ntp_list_item_text_size">16sp</dimen>
     <dimen name="ntp_shadow_height">9dp</dimen>
+    <dimen name="ntp_min_bottom_spacing_recycler_view">32dp</dimen>
     <dimen name="snippets_thumbnail_size">72dp</dimen>
     <dimen name="snippets_padding_and_peeking_card_height">16dp</dimen>
     <dimen name="snippets_card_9_patch_adjustment">2dp</dimen>
     <dimen name="snippets_article_header_height">40dp</dimen>
     <dimen name="snippets_card_elevation">2dp</dimen>
 
     <!-- Interests page -->
     <dimen name="ntp_interest_item_text_size">20sp</dimen>
     <dimen name="ntp_interest_item_min_height">180dp</dimen>
     <dimen name="ntp_interest_item_image_size">120dp</dimen>
@@ skipping 69 matching lines @@
          padding set.
     -->
     <dimen name="pref_autofill_content_padding">12dp</dimen>
     <dimen name="pref_autofill_field_horizontal_padding">4dp</dimen>
     <dimen name="pref_autofill_field_top_padding">10dp</dimen>
 
     <!-- Dialog dimensions.
          https://www.google.com/design/spec/components/dialogs.html#dialogs-simple-dialogs -->
     <dimen name="dialog_width_unit">56dp</dimen>  <!-- MD dialog widths are multiples of this. -->
 </resources>